PROJECT SUMMARY The risk of patient harm is increasing as the healthcare system becomes more complex. Despite a decade of intense scrutiny and many attempts to impact these refractory challenges, there remains a need to refine and explore strategies to hard-wire a culture of patient safety among front-line healthcare workers. A recently disseminated strategy is Team Strategies and Tools to Enhance Performance and Patient Safety (TeamSTEPPSTM). TeamSTEPPS was developed through a partnership of AHRQ and the Department of Defense to improve healthcare team performance through flexible training designed to enhance team knowledge, skills, and attitudes. TeamSTEPPS involves a comprehensive curriculum that spells out key actions for a culture change of teamwork including: team leadership, mutual performance monitoring, back-up behaviors, adaptability, team/collective orientation, shared mental models, mutual trust, and closed-loop communication. AHRQ is actively disseminating TeamSTEPPS through national training centers. Although firmly based in research findings on the operations and effectiveness of teamwork, many aspects of the TeamSTEPPS approach have not yet been evaluated. There remains a need to ground team performance within organizational science to facilitate the exploration and testing of relationships among the TeamSTEPPS elements and organizational performance. Thus, the purpose of this study is to examine the relationship between key TeamSTEPPS elements and outcomes through considering both retrospective and prospective implementations in hospitals chosen to represent a cross-section of complexity (Critical Access Hospital vs. nonCAH) and affiliation (independent vs. owned/managed by a system). Multi-method approaches will be used to monitor the TeamSTEPPS application to the Complex Adaptive Systems (CAS) of microsystems in a variety of hospital units. The specific aims are to: 1) Explicate organizational elements that have facilitated or precluded full integration of the TeamSTEPPS model in 10 hospital units that have previously adopted the model; 2) Prospectively examine the process and outcomes of implementing TeamSTEPPS in 12 hospitals chosen to represent a cross-section of complexity (Critical Access Hospital vs. nonCAH) and affiliation (independent vs. owned/managed by a system); 3) Test the relationship between TeamSTEPPS measures (patient safety culture, teamwork attitudes and performance, initiative fidelity, and observed knowledge-skills- attitude (KSA) behaviors) and outcomes over time; and 4) Identify the TeamSTEPPS strategies that are most successful in terms of positive outcomes and the characteristics of a high reliability organization and then determine the burden and cost of implementing these successful strategies.